Gas turbine engine systems for modern aircraft often include a thrust reverser incorporated into a nacelle. The thrust reverser may redirect the flow of air through the nacelle in order to apply a reverse thrust to the aircraft. One style of thrust reverser includes a translating sleeve. The translating sleeve may translate aft to deploy blocker doors into the bypass air duct of a nacelle. The blocker doors may redirect air in the bypass air duct outward though a series of cascades which then turn the air forward, producing reverse thrust. The blocker doors typically may be hinged to the translating sleeve and coupled to the inner fixed structure via a drag link. As the translating sleeve translates aft, the drag link pulls the blocker doors inward, pivoting them into the bypass air duct.
In some existing thrust reversers, the blocker door includes acoustic treatment to help damp noise created by the propulsion system. In that case, thrust reverser blocker doors have been constructed as acoustic sandwich panels with a top skin, back skin, and a core layer, such as a honeycomb core, layered in between to create resonating chambers that cancel noise in a known manner.
In the past, acoustic sandwich panel blocker doors were constructed as bonded metallic structures. Today, they may be constructed using laminar composites for the skins, and aluminum foil, paper, or similar core for the core layer. But the construction methods can be expensive. Forming the skins using laminar composites may require autoclave curing. The core must be carefully trimmed and cut to shape. All of these operations require extensive time and capital-intensive equipment. A new construction method and design is needed to reduce the cost of acoustic blocker doors in a thrust reverser.